Will is pretty hard to shorten. But you could use Willie.
Famous people named Will:
Actors Will Smith, Will Rogers, Will Ferrell, Will Arnett, Will Forte, and Will Geer; novelist Will Self; songwriter Will Jennings; drummer Will Champion; football player Will Allen.
In the popular 2018 movie Dumplin', the main character is Willowdean Dickson - called Will by her friends.
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